Alpha-Synuclein Oligomers and Neurofilament Light Chain in Spinal Fluid Differentiate Multiple System Atrophy from Lewy Body Synucleinopathies.
脊髓液中的 α-Synuclein 寡聚体和神经丝轻链将多系统萎缩与 Lewy 小体 Synuclein 病区分开来。
- 作者列表："Singer W","Schmeichel AM","Shahnawaz M","Schmelzer JD","Boeve BF","Sletten DM","Gehrking TL","Gehrking JA","Olson AD","Savica R","Suarez MD","Soto C","Low PA
OBJECTIVE:To explore the role of alpha-synuclein (αSyn) oligomers and neurofilament light chain (NFL) in cerebrospinal fluid (CSF) as markers of early multiple system atrophy (MSA) and to contrast findings to Lewy body synucleinopathies. METHODS:In a discovery cohort of well-characterized early MSA patients (n = 24) and matched healthy controls (CON, n = 14) we utilized ELISA to measure NFL and protein misfolding cyclic amplification (PMCA) to detect αSyn oligomers in CSF. We confirmed findings in a separate prospectively enrolled cohort of patients with early MSA (n = 38), Parkinson's disease (PD, n = 16), dementia with Lewy bodies (DLB, n = 13), and CON subjects (n = 15). RESULTS:In the discovery cohort, NFL was markedly elevated in MSA patients with perfect separation from CON. ASyn-PMCA was non-reactive in all CON, while all MSA samples were positive. In the confirmatory cohort, NFL again perfectly separated MSA from CON, and was significantly lower in PD and DLB compared to MSA. PMCA was again non-reactive in all CON, and positive in all but 2 MSA cases. All PD and all but 2 DLB samples were also positive for αSyn aggregates but with markedly different reaction kinetics than MSA: aggregation occurred later but maximum fluorescence was higher, allowing for perfect separation of reactive samples between MSA and Lewy body synucleinopathies. INTERPRETATION:NFL and αSyn oligomers in CSF faithfully differentiate early MSA not only from CON but also from Lewy body synucleinopathies. The findings support the role of these markers as diagnostic biomarkers, and have important implications for understanding pathophysiologic mechanisms underlying the synucleinopathies. This article is protected by copyright. All rights reserved.
目的: 探讨脑脊液 (CSF) 中 α-突触核蛋白 (α syn) 寡聚体和神经丝轻链 (NFL) 作为早期多系统萎缩 (MSA) 标志物的作用。并将结果与路易体突触核蛋白病进行对比。 方法: 在特征明确的早期 MSA 患者 (n = 24) 和匹配的健康对照 (CON，n = 14) 的发现队列中我们利用 ELISA 测定 NFL 和蛋白错误折叠循环扩增 (PMCA) 检测 CSF 中的 α syn 寡聚体。我们在独立的前瞻性入组的早期 MSA (n = 38) 、帕金森病 (PD，n = 16) 、路易体痴呆 (DLB, n = 13) 和 CON 受试者 (n = 15)。 结果: 在 discovery 队列中，与 CON 完全分离的 MSA 患者 NFL 显著升高。ASyn-PMCA 在所有 CON 中均无反应，而所有 MSA 样本均为阳性。在验证性队列中，NFL 再次将 MSA 与 CON 完美分离，与 MSA 相比，PD 和 DLB 显著较低。PMCA 在所有 CON 中再次无反应，在除 2 例 MSA 病例外的所有病例中均呈阳性。所有 PD 和除 2 个 DLB 样品外的所有样品 α syn 聚集体也呈阳性，但反应动力学与 MSA 明显不同: 聚集发生较晚，但最大荧光较高,允许 MSA 和 Lewy 体突触核蛋白病之间反应性样本的完美分离。 解读: CSF 中的 NFL 和 α syn 寡聚体忠实地区分早期 MSA 不仅与 CON，而且与 Lewy 小体突触核蛋白病。这些发现支持这些标志物作为诊断生物标志物的作用，并对理解突触核蛋白病的病理生理机制具有重要意义。本文受版权保护。保留所有权利。
METHODS::Identifying disease-causing pathways and drugs that target them in Parkinson's disease (PD) has remained challenging. We uncovered a PD-relevant pathway in which the stress-regulated heterodimeric transcription complex CHOP/ATF4 induces the neuron prodeath protein Trib3 that in turn depletes the neuronal survival protein Parkin. Here we sought to determine whether the drug adaptaquin, which inhibits ATF4-dependent transcription, could suppress Trib3 induction and neuronal death in cellular and animal models of PD. Neuronal PC12 cells and ventral midbrain dopaminergic neurons were assessed in vitro for survival, transcription factor levels and Trib3 or Parkin expression after exposure to 6-hydroxydopamine or 1-methyl-4-phenylpyridinium with or without adaptaquin co-treatment. 6-hydroxydopamine injection into the medial forebrain bundle was used to examine the effects of systemic adaptaquin on signaling, substantia nigra dopaminergic neuron survival and striatal projections as well as motor behavior. In both culture and animal models, adaptaquin suppressed elevation of ATF4 and/or CHOP and induction of Trib3 in response to 1-methyl-4-phenylpyridinium and/or 6-hydroxydopamine. In culture, adaptaquin preserved Parkin levels, provided neuroprotection and preserved morphology. In the mouse model, adaptaquin treatment enhanced survival of dopaminergic neurons and substantially protected their striatal projections. It also significantly enhanced retention of nigrostriatal function. These findings define a novel pharmacological approach involving the drug adaptaquin, a selective modulator of hypoxic adaptation, for suppressing Parkin loss and neurodegeneration in toxin models of PD. As adaptaquin possesses an oxyquinoline backbone with known safety in humans, these findings provide a firm rationale for advancing it towards clinical evaluation in PD.
METHODS::Huntington's disease (HD) is an inherited progressive neurodegenerative disease characterized by brain atrophy particularly in the striatum that produces motor impairment, and cognitive and psychiatric disturbances. Multiple pathogenic mechanisms have been proposed including dysfunctions in neurotrophic support and calpain-overactivation, among others. Kinase D-interacting substrate of 220 kDa (Kidins220), also known as ankyrin repeat-rich membrane spanning (ARMS), is an essential mediator of neurotrophin signaling. In adult brain, Kidins220 presents two main isoforms that differ in their carboxy-terminal length and critical protein-protein interaction domains. These variants are generated through alternative terminal exon splicing of the conventional exon 32 (Kidins220-C32) and the recently identified exon 33 (Kidins220-C33). The lack of domains encoded by exon 32 involved in key neuronal functions, including those controlling neurotrophin pathways, pointed to Kidins220-C33 as a form detrimental for neurons. However, the functional role of Kidins220-C33 in neurodegeneration or other pathologies, including HD, has not been explored. In the present work, we discover an unexpected selective downregulation of Kidins220-C33, in the striatum of HD patients, as well as in the R6/1 HD mouse model starting at early symptomatic stages. These changes are C33-specific as Kidins220-C32 variant remains unchanged. We also find the early decrease in Kidins220-C33 levels takes place in neurons, suggesting an unanticipated neuroprotective role for this isoform. Finally, using ex vivo assays and primary neurons, we demonstrate that Kidins220-C33 is downregulated by mechanisms that depend on the activation of the protease calpain. Altogether, these results strongly suggest that calpain-mediated Kidins220-C33 proteolysis modulates onset and/or progression of HD.
METHODS:BACKGROUND:Neuroinflammation has been recognized as an important factor in the pathogenesis of Alzheimer's disease (AD). One of the most recognized pathways in mediating neuroinflammation is the prostaglandin E2-EP1 receptor pathway. OBJECTIVE:Here, we examined the efficacy of the selective EP1 antagonist ONO-8713 in limiting amyloid-β (Aβ), lesion volumes, and behavioral indexes in AD mouse models after ischemic stroke. METHODS:Transgenic APP/PS1, 3xTgAD, and wildtype (WT) mice were subjected to permanent distal middle cerebral artery occlusion (pdMCAO) and sham surgeries. Functional outcomes, memory, anatomical outcomes, and Aβ concentrations were assessed 14 days after surgery. RESULTS:pdMCAO resulted in significant deterioration in functional and anatomical outcomes in the transgenic mice compared with the WT mice. No relevant differences were observed in the behavioral tests when comparing the ONO-8713 and vehicle-treated groups. Significantly lower cavitation (p = 0.0373) and percent tissue loss (p = 0.0247) were observed in APP/PS1 + ONO-8713 mice compared with the WT + ONO-8713 mice. However, the percent tissue injury was significantly higher in APP/PS1 + ONO-8713 mice compared with WT + ONO-8713 group (p = 0.0373). Percent tissue loss was also significantly lower in the 3xTgAD + ONO-8713 mice than in the WT + ONO-8713 mice (p = 0.0185). ONO-8713 treatment also attenuated cortical microgliosis in APP/PS1 mice as compared with the vehicle (p = 0.0079); however, no differences were observed in astrogliosis across the groups. Finally, APP/PS1 mice presented characteristic Aβ load in the cortex while 3xTgAD mice exhibited very low Aβ levels. CONCLUSION:In conclusion, under the experimental conditions, EP1 receptor antagonist ONO-8713 showed modest benefits on anatomical outcomes after stroke, mainly in APP/PS1 mice.